Browse wiki
Jump to navigation
Jump to search
On October 13, 2001 Unit 1 was shutdown in … On October 13, 2001 Unit 1 was shutdown in Mode 6 in refueling outage 1RE10. Information was received from an offsite vendor that during pressurizer safety valve "as found" set point testing, valve N1RCPSV3451 had a lift pressure of 2406 psig which is low outside of the Technical Specification required setpoint of 2485 psig +/-2% (2435.3 to 2534.7). Valve N1RCPSV3452 had an "as found" lift pressure of 2411 psig. On October 15, 2001 the vendor reported that safety valve N1RCPSV3450 had an "as found" lift pressure of 2422 psig. These test results constitute a violation of Technical Specification 3.4.2.2, Reactor Coolant System - Operating. The root causes of the valves failing the "as found" lift tests include: (a) the inherent differences between the "as left' test conditions and the "as found" test conditions, plus nozzle loading effects which are inducing stresses and misalignments in the valves, and (b) the narrow tolerance band of +/- 2% which is too restrictive considering the valve nozzle loading effects and these inherent differences. Corrective actions include installation of replacement valves with "as left' lift settings of 2485 psig +/- 1%, and requesting a Technical Specification change to optimize setpoint tolerances for the Pressurizer Safety Valves "as found" lift setpoints.</br></br>The "as found" Pressurizer Safety Valve setpoints did not violate any safety analysis limits and did not adversely impact Reactor Coolant System overpressurization or Departure from Nucleate Boiling Ratio analysis.ture from Nucleate Boiling Ratio analysis. +
October 13, 2001 +
On October 13, 2001 Unit 1 was shutdown in … On October 13, 2001 Unit 1 was shutdown in Mode 6 in refueling outage 1RE10. Information was received from an offsite vendor that during pressurizer safety valve "as found" set point testing, valve N1RCPSV3451 had a lift pressure of 2406 psig which is low outside of the Technical Specification required setpoint of 2485 psig +/-2% (2435.3 to 2534.7). Valve N1RCPSV3452 had an "as found" lift pressure of 2411 psig. On October 15, 2001 the vendor reported that safety valve N1RCPSV3450 had an "as found" lift pressure of 2422 psig. These test results constitute a violation of Technical Specification 3.4.2.2, Reactor Coolant System - Operating. The root causes of the valves failing the "as found" lift tests include: (a) the inherent differences between the "as left' test conditions and the "as found" test conditions, plus nozzle loading effects which are inducing stresses and misalignments in the valves, and (b) the narrow tolerance band of +/- 2% which is too restrictive considering the valve nozzle loading effects and these inherent differences. Corrective actions include installation of replacement valves with "as left' lift settings of 2485 psig +/- 1%, and requesting a Technical Specification change to optimize setpoint tolerances for the Pressurizer Safety Valves "as found" lift setpoints.</br></br>The "as found" Pressurizer Safety Valve setpoints did not violate any safety analysis limits and did not adversely impact Reactor Coolant System overpressurization or Departure from Nucleate Boiling Ratio analysis.ture from Nucleate Boiling Ratio analysis. +
Has query"Has query" is a predefined property that represents meta information (in form of a <a rel="nofollow" class="external text" href="https://www.semantic-mediawiki.org/wiki/Subobject">subobject</a>) about individual queries and is provided by <a rel="nofollow" class="external text" href="https://www.semantic-mediawiki.org/wiki/Help:Special_properties">Semantic MediaWiki</a>.
2 +
Modification date"Modification date" is a predefined property that corresponds to the date of the last modification of a subject and is provided by <a rel="nofollow" class="external text" href="https://www.semantic-mediawiki.org/wiki/Help:Special_properties">Semantic MediaWiki</a>.
04:13:56, 1 December 2017 +
December 12, 2001 +
October 13, 2001 +
Texas + and South Carolina +
URL"URL" is a <a href="/Special:Types/URL" title="Special:Types/URL">type</a> and predefined property provided by <a rel="nofollow" class="external text" href="https://www.semantic-mediawiki.org/wiki/Help:Special_properties">Semantic MediaWiki</a> to represent URI/URL values.